对引起柑桔黄龙病的类菌原体（ＢＬＯ）的ＰＣＲ检测方法进行了研究．结果表明，利用ＰＣＲ方法不但能对ＢＬＯ、ＤＮＡ进行离体扩增，而且对各种不同来源的感病植物样品也能很好地进行检测．本文首次报道了从未显症的植物上用ＰＣＲ方法检测到了ＢＬＯ，技接试验证实了该方法的可靠性．正是由于本方法可在病原侵染早期进行检测这一优点，从而可控制带病苗木的扩散．该技术也可被用于无毒苗木的筛选，从而控制病害发生．该技术对ＢＬＯ引起的黄龙病的检测不但简单、有效而且实用 The method of PCR detection of the genus Mycoplasma (BLO) causing citrus Huanglongbing was studied. The results showed that the PCR method can not only amplify the BLO and DNA in vitro, but also detect the samples of various infected plants from different sources. This paper reports for the first time that BLO has been detected by PCR in plants that have never seen any symptoms, and the technical test confirms the reliability of this method. It is the advantage of this method that it can be detected early in the pathogen infection to control the spread of diseased seedlings. The technology can also be used to screen nontoxic seedlings to control disease. The technology of BLO caused by the detection of yellow dragon is not only simple, effective and practical